The electrical resistivity ρ, the thermopower S and the magnetic susceptibility χ = M/B of the ternary compound EuNiGe 3 with the BaNiSn 3 -type structure have been measured at temperatures from 2 to 300 K. The measurements of ρ and S have been performed under pressures up to 1.8 GPa, together with ρ under pressures up to 8 GPa. With increasing temperature, the magnetic susceptibility χ shows a drastic increase, having a peak at the Néel temperature T N = 14 K and indicating the Curie-Weiss behavior at high temperature region. The effective magnetic moment of EuNiGe 3 is µ eff ≈ 7.7 µ B /Eu, indicating the 4f 7 (Eu 2+ ) electron configuration. The Néel temperature T N obtained from ρ(T ) and S (T ) curves increases linearly with increasing pressure. It is considered that the electron density of states of EuNiGe 3 in the vicinity of the Fermi energy has a small value and a weak energy dependence, and the Eu 2+ electronic configuration is stable.

The electrical resistivity and thermopower of light-and heavy-rare-earth-based pseudo-binary Y 1Àx R x Co 2 (R = Nd, Gd, and Tb) alloys are measured at temperatures from 2 to 300 K under pressures up to 3.5 GPa. The resistivity and thermopower of Y 1Àx R x Co 2 show unusual large variations with atomic substitution and pressure in the range of x < x m , where an inhomogeneous magnetization of the Co 3d electron subsystem is observed. These results indicate that the low-temperature transport properties of Y 1Àx Nd x Co 2 , as well as of Y 1Àx R Hx Co 2 (R H = heavy rare earth) alloys, are related to conduction electron scattering due to the static magnetic disorder in the itinerant Co 3d electron subsystem. We found that there is a universal relationship between d ln T C =dP and x=x m in Y 1Àx R x Co 2 alloys, where x m is the boundary composition, which separates the alloy phase diagram into regions with uniform and nonuniform magnetizations of the Co-3d electron subsystem.

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